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991.
The linear increment of Sphagnum fuscum and S. magellanicum in ombrotrophic mires of Western Siberia has been measured during two years over a transect about 2500 km long extending from forest–steppe to forest–tundra. Along the latitudinal gradient, the increment of both species has proved to be correlated with annual average air temperature and, in S. magellanicum, also with annual precipitation. The determinants of their growth differ between the southern, central, and northern parts of the study region. At the regional level, the annual and summer precipitation plays a more important role than the average air temperature. The increment of S. fuscum in the southern part is positively correlated with the amount of precipitation and negatively correlated with summer temperature, whereas the situation in the central part is inverse. In S. magellanicum, the linear increment is directly dependent on the annual average temperature and annual and summer precipitation in the south and on the annual and summer precipitation in the north of Western Siberia. The dynamics of linear growth of both species in bog pine forests during the growing season are similar: its rate is the highest in June, when the linear increment of S. fuscum and S. magellanicum amounts to 60 and 85% of the annual total, respectively. 相似文献
992.
Trends in the dynamics of herbivore community related to trophic competition in summer have been analyzed on Wrangel Island. The results show that the trophic spectra overlap considerably, resources are partitioned on the principle “weak competitors after strong competitors,” and community dynamics in the absence of extermination depend on specific competitive advantages related to the width of food spectrum. We conclude that the dynamics of this insular community prior to the establishment of nature reserve on the island have been determined by human activities, as well as the structure of arctic herbivore communities in general. 相似文献
993.
Evelien?M.?de OldeEmail author Henrik?Moller Fleur?Marchand Richard?W.?McDowell Catriona?J.?MacLeod Marion?Sautier Stephan?Halloy Andrew?Barber Jayson?Benge Christian?Bockstaller Eddie?A.?M.?Bokkers Imke?J.?M.?de Boer Katharine?A.?Legun Isabelle?Le Quellec Charles?Merfield Frank?W.?Oudshoorn John?Reid Christian?Schader Erika?Szymanski Claus?A.?G.?S?rensen Jay?Whitehead Jon?Manhire 《Environment, Development and Sustainability》2017,19(4):1327-1342
Sustainability indicators are well recognized for their potential to assess and monitor sustainable development of agricultural systems. A large number of indicators are proposed in various sustainability assessment frameworks, which raises concerns regarding the validity of approaches, usefulness and trust in such frameworks. Selecting indicators requires transparent and well-defined procedures to ensure the relevance and validity of sustainability assessments. The objective of this study, therefore, was to determine whether experts agree on which criteria are most important in the selection of indicators and indicator sets for robust sustainability assessments. Two groups of experts (Temperate Agriculture Research Network and New Zealand Sustainability Dashboard) were asked to rank the relative importance of eleven criteria for selecting individual indicators and of nine criteria for balancing a collective set of indicators. Both ranking surveys reveal a startling lack of consensus amongst experts about how best to measure agricultural sustainability and call for a radical rethink about how complementary approaches to sustainability assessments are used alongside each other to ensure a plurality of views and maximum collaboration and trust amongst stakeholders. To improve the transparency, relevance and robustness of sustainable assessments, the context of the sustainability assessment, including prioritizations of selection criteria for indicator selection, must be accounted for. A collaborative design process will enhance the acceptance of diverse values and prioritizations embedded in sustainability assessments. The process by which indicators and sustainability frameworks are established may be a much more important determinant of their success than the final shape of the assessment tools. Such an emphasis on process would make assessments more transparent, transformative and enduring. 相似文献
994.
Suescún Diego Villegas Juan Camilo León Juan Diego Flórez Claudia P. García-Leoz Vanessa Correa-Londoño Guillermo A. 《Regional Environmental Change》2017,17(3):827-839
Regional Environmental Change - Mountain ecosystems provide key services to a large portion of the population in the tropics. However, they are particularly vulnerable to regional environmental... 相似文献
995.
Huber Nica Hergert Rico Price Bronwyn Zäch Christian Hersperger Anna M. Pütz Marco Kienast Felix Bolliger Janine 《Regional Environmental Change》2017,17(4):1241-1255
Regional Environmental Change - Replacement of conventional energy sources with renewables such as solar panels and wind turbines requires adequate land. Impact assessments should be conducted to... 相似文献
996.
Philip Antwi-Agyei Claire Helen Quinn Samuel Godfried Kwasi Adiku Samuel Nii Ardey Codjoe Andrew John Dougill Richard Lamboll Delali Benjamin Komla Dovie 《Regional Environmental Change》2017,17(1):213-227
Smallholder farmers in sub-Saharan Africa are confronted with climatic and non-climatic stressors. Research attention has focused on climatic stressors, such as rainfall variability, with few empirical studies exploring non-climatic stressors and how these interact with climatic stressors at multiple scales to affect food security and livelihoods. This focus on climatic factors restricts understanding of the combinations of stressors that exacerbate the vulnerability of farming households and hampers the development of holistic climate change adaptation policies. This study addresses this particular research gap by adopting a multi-scale approach to understand how climatic and non-climatic stressors vary, and interact, across three spatial scales (household, community and district levels) to influence livelihood vulnerability of smallholder farming households in the Savannah zone of northern Ghana. This study across three case study villages utilises a series of participatory tools including semi-structured interviews, key informant interviews and focus group discussions. The incidence, importance, severity and overall risk indices for stressors are calculated at the household, community, and district levels. Results show that climatic and non-climatic stressors were perceived differently; yet, there were a number of common stressors including lack of money, high cost of farm inputs, erratic rainfall, cattle destruction of crops, limited access to markets and lack of agricultural equipment that crossed all scales. Results indicate that the gender of respondents influenced the perception and severity assessment of stressors on rural livelihoods at the community level. Findings suggest a mismatch between local and district level priorities that have implications for policy and development of agricultural and related livelihoods in rural communities. Ghana’s climate change adaptation policies need to take a more holistic approach that integrates both climatic and non-climatic factors to ensure policy coherence between national climate adaptation plans and District development plans. 相似文献
997.
Stephanie K. H. Janssen Jan P. M. van Tatenhove Arthur P. J. Mol Henriëtte S. Otter 《Regional Environmental Change》2017,17(2):551-563
Greening flood protection (GFP) is increasingly recognized as an adaptive and flexible approach to water management that is well suited to addressing uncertain futures associated with climate change. In the last decade, GFP knowledge and policies have developed rapidly, but implementation has been less successful and has run into numerous barriers. In this paper, we address the challenge of realizing green flood protection goals by specifically considering knowledge in the decision-making of a Dutch flood protection project in Lake Markermeer. In this project, an ecological knowledge arrangement and a traditional flood protection knowledge arrangement are compared and their interactions analysed. The analysis provides insight into the specific difficulties of implementing GFP measures and identifies ways to realize GFP goals. The primary challenge is twofold: First, a self-reinforcing cycle of knowledge production and decision-making in the flood protection domain inhibits the introduction of innovative and multifunctional approaches such as GFP; second, the distribution of power is severely unbalanced in terms of ecological enhancement and flood protection, favouring the latter. Implementation of GFP requires structural change and the integration of ecological and flood protection knowledge and policy. Potentially rewarding routes towards this integration are the exploration of shared interests in GFP and the creation of mutual dependency between knowledge arrangements. The case study and the insights it provides show that GFP is far from mainstream practice and that implementation requires serious effort and courage to break with historical practices. 相似文献
998.
Maurer Edwin P. Roby Nicholas Stewart-Frey Iris T. Bacon Christopher M. 《Regional Environmental Change》2017,17(8):2421-2432
Regional Environmental Change - In addition to periodic long-term drought, much of Central America experiences a rainy season with two peaks separated by a dry period of weeks to over a month in... 相似文献
999.
P. Thamsatitdej S. Boon-itt P. Samaranayake M. Wannakarn 《International Journal of Sustainable Engineering》2017,10(6):326-337
Due to increasing emphasis on sustainable practices, many organisations have attempted to leverage their supply chain performance towards balancing triple bottom line dimensions (economic, environmental and social perspectives). This paper, therefore, determines the priorities of sustainable supply chain management focusing on eco-design. Interpretive structural modelling (ISM) and Matriced’ Impacts Croise’s Multiplication Appliquée a UN Classement (MIMAC) are used to identify the hierarchical structure of the relationships among eco-design dimensions, and to analyse characteristics power of each dimension on supporting eco-design practices. The relationships and characteristics power of each dimension are used to determine indicators that are effective in enhancement of eco-design practice, evaluated through sustainable supply chain performance. Results indicate that product deployment is an important approach for improving eco-design practice towards sustainable supply chain management. This emphasises the purpose and impact of eco-design on sequential supply chain activities at deployment phase. Further research is required to make an overall assessment of eco-design practices across range of manufacturing industries, given the current research is based on inputs from a limited number of experts of selected organisations. 相似文献
1000.
A. R. T. S. Araujo M. C. Sarraguça M. P. Ribeiro P. Coutinho 《Environmental geochemistry and health》2017,39(3):483-496
Mineral natural waters and spas have been used for therapeutic purposes for centuries, with Portugal being a very rich country in thermal waters and spas that are mainly distributed by northern and central regions where Beira Interior region is located. The use of thermal waters for therapeutic purposes has always been aroused a continuous interest, being dependent on physicochemical fingerprinting of this type of waters the indication for a treatment in a specific pathological condition. In the present work, besides a literature review about the physicochemical composition of the thermal waters of the Beira Interior region and its therapeutic indications, it was carried out an exhaustive multivariate analysis—principal component analysis and cluster analysis—to assess the correlation between different physicochemical parameters and the therapeutic indications claims described for these spas and thermal waters. These statistical methods used for data analysis enables classification of thermal waters compositions into different groups, regarding to the different variable selected, making possible an interpretation of variables affecting water compositions. Actually, Monfortinho and Longroiva are clearly quite different of the others, and Cró and Fonte Santa de Almeida appear together in all analysis, suggesting a strong resemblance between these waters. Thereafter, the results obtained allow us to demonstrate the role of major components of the studied thermal waters on a particular therapeutic purpose/indication and hence based on compositional and physicochemical properties partially explain their therapeutic qualities and beneficial effects on human health. This classification agreed with the results obtained for the therapeutic indications approved by the Portuguese National Health Authority and proved to be a valuable tool for the regional typology of mineral medicinal waters, constituting an important guide of the therapeutic armamentarium for well and specific-oriented pathological disturbs. 相似文献